2010 Construction and Material Specifications - Ohio Department of ...

427
602.03
602.03 Construction Requirements. Construct the designated items as shown
on the plans.
A. Excavate to dimensions that provide ample room for construction. Remove
obstructions as necessary to perform this work.
Protect the sides of all excavations from caving by providing suitable sheeting,
shoring, and bracing. Use excavation methods that do not disturb the original
material below the bottom of footers or below the additional 6 inches (150 mm)
required for precast structures.
If the material found at the bottom of the headwall or below the additional 6
inches (150 mm) required for precast structures is not suitable for a foundation,
excavate to further depth to provide a suitable foundation. Backfill the void left by
the additional excavation with granular base. The Department will pay for this
additional work according to 109.05.
Backfilling shall follow completion of the work as closely as the construction
will allow. Backfill with granular base or soil. Place backfill in 6-inch (150 mm)
loose lifts.
B. Compaction requirements are according to Item 203 except for the following:
Four passes per lift with additional passes as required until 95 percent
compaction is reached. Use compaction equipment with a minimum total weight
of, or minimum centrifugal force of, 1 ton (0.9 metric ton). Supply the
manufacturer’s specifications for this equipment to verify these requirements.
C. Cast-in-place structures are headwalls, pipe cradles, collars, and other units.
Construct cast-in-place structures according to the corresponding Standard
Construction Drawing using methods specified in Items 499, 511, and 509.
D. Pre-cast structures are half height headwalls for conduits up to a maximum
of 78 inches (1980 mm). These pre-approved pre-cast structure drawings are on
file in the Office Material Management. With the submission of the TE-24 from an
approved manufacturer furnish stamped, approved from the Office of Structural
Engineering design drawing sheets. Pre-cast half-height headwalls for elliptical
and pipe arch conduits may be constructed from templates of the actual conduit
being supplied, up to a maximum 78 inch (1980 mm) (round equivalent) to the
project to ensure the opening is OD plus one inch. Submit drawings to the Office
of Structural Engineering for approval, on a project by project basis, of pre-cast
half-height headwalls for elliptical and pipe arch conduit. Non-pre-approved
drawings are required to be submitted to the Office of Structural Engineering for
approval. Allow 4 weeks for approval. Failure to furnish the stamped, approved
design drawing sheets will result in rejection of the pre-cast structure. The
drawings will include the following:
1. All manufacturers are pre-approved per Supplement 1073.
2. All reinforcing steel will be epoxy coated.
3. All HW-2.1 SCD require wire insert details.
4. Attachment detail for metal or plastic conduit per SCD HW2.1.